350/330 Crate engine mods? You`ve seem to been
at nearly same type situation. Like to hear your opinion?

S-24

i don't understand what you mean by situation? am i missing something....

i started off with a 350 2V 250 pshp motor... i now make about 380 pshp... the only thing original is my rotating assembly...

if you would like to know what i've done i can expound on that.

i assume this crate motor is a "MARINE" application crate motor???

as far as exhaust i run stock merc center riser with imco ss risers. straight thru-hull and no thru-prop.... i run too much camshaft to run thru-prop without sucking up water.

i cannot find any dyno comparisons for sbc aftermarket exhasut to sell me on the price tag for performance gain. I've watched people swap stock merc for SM and gain nothing on a sbc...

in michigan we have a noise law too of 90 dBA.... i am at 104 at idle.. 3 feet from the transom between the pipes... i say... F'em if they can't take a joke but then again the speed limit is 55 mph too

Jamie

It is car crate engine, so I have to change the freeze plugs and head gaskets, which I have to make anyway,
because of the cam swap. I`d like to know the parts
you`re using for that power? Didn´t you ran earlier thru-prop? So you`re using stock manifolds w/ss risers, for
reversion. Notice any gains, other than not getting water back,vs.cast risers? And better sound
Engine is basically same, as yours was, except
it comes w/flat tappet cam. That`s what I meant
with same situation, vortec heads, not stroker, as
most sb engines here. Advise on do`s/dont, would be very appreciated.

Thanks, s-24

ok lets see...

combination.

2 Bolt GM Roller Cam Block
Melling HV Oil Pump
ARP Steel Oil Pump Driveshaft
Windage Tray
Stock GM Oil Pan and Pickup
GM Cast Crank
GM PM Rods
ARP Rod Bolts
ARP Main Studs
GM Balancer
GM Flywheel
GM Starter
GM Fuel Pump
GM Hypereutectic 13 CC dished pistons
GM Piston Rings
GM Steel shim head gaskets @ .015 inch thickness sealed with Hi-Tack
9.4:1 static Compression Ratio
Pro-Action 220 CC Cast port cylinder heads with port match.
Manley (Eaton) Severe Duty SS 2.02/1.60 valves + .100 stem length
Comp Teflon Valveguide Seals
Comp 986 Springs, spring seats, shims, Retainers and steel locks
Comp 1.52:1 roller tip rockers
ARP Rocker Studs
ARP Head Studs
Comp Cams XM276HR Roller @ 4 degrees retarded
Comp Pushrods
Stock GM Roller Lifters, tiebars and spider
Comp Cams double roller timing chain
Edelbrock RPM air-gap intake manifold
750 cfm Demon
Holley fuel pressure regulator
MSD Pro-Billet distributor
MSD Plug Wires
MSD Digital 6+ Box
MSD SHift Assist
Stock Merc center riser manifolds
IMCO Stainless M-72 risers
Stock Merc 160* Thermostat

basically i have a stock rotating assembly right from Merc/ GM...

i have NEVER run thru-prop on my boat.. it came thru-hull from the factory.

i cannot say what the risers gave me for power. i did other motor work at the same time...

i can spin a 25 pitch 14 3/4 hydromotive 4 blade nearly 5800 rpm with a 1.59:1 ratio drive (yes you read that ratio correctly)... i need more pitch to suck her back to 5500 or a bit less...

one other thing you need to be aware of.. marine engines and auto engines have different piston to bore clearances and top piston ring gap is larger on a marine engine... if it was me i'd take it apart and regap the rings...

Well ´cause I`m changing the cam I might take it apart and check the ring gaps as well. Thanks for advise, I knew there was something I havent considered, there
sure are other things, but I believe I`ll find them here.

Thank you very much,
s-24

Rootser....you left out the corvette valve covers

thanks rick... Can't forget the vette valve covers well until i get some time to cut my custom ones....